Between Electron `0.30.x` and `0.37.x`, the tray icon stopped automatically inverting template images when highlighted. NSImageView normally uses the correct color for template images magicaly, but I think the addition of event handlers in the container view prevents the image view from determining highlight state.
This PR switches to drawing the image manually. The `drawRect` function decides whether to use `image` or `alternateImage`(pressed image) and then if that image is marked as a template, it fills it with the same color used for the text before drawing it.
f9644463a9